P261A
Coolant Pump B Control Circuit / Open
The controller cannot drive the second electric coolant pump (B). Often used for aftertreatment, turbo cool-down, or hybrid battery loops — fault stops circulation in that loop.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Open pump motor windingCommon
- Broken control wire to the pumpPossible
Parts involved
- Coolant Pump B
- Pump Relay
- Wiring Harness
P261A is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.